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Numerical study on anti-impact characteristics of energy absorbing column with multicellular square tube filled with aluminum foam [PDF]
Aiming at the insufficient anti-impact performance of existing components of the energy-absorbing anti-impact support, a foam aluminum filled multicellular square tube structure is proposed.
Heng ZHU +5 more
core +1 more source
Experimental study on energy dissipation and failure characteristics of rock at depth under non-hydrostatic pressure condition [PDF]
Deep buried rock is often in a non-hydrostatic initial ground stress field, and the different stress states lead to different rock response under dynamic loading.
Jun CHEN +4 more
core +1 more source
多元纳米稀土六硼化物Nd 1– x Eu x B 6 粉末的制备及光吸收研究
在真空环境中采用固相烧结法成功制备出了多元稀土六硼化物Nd1–xEuxB6纳米粉末. 系统研究了Eu掺杂对纳米NdB6物相、形貌及光吸收性能的影响规律. 结果表明, 所有合成的纳米粉末物相均为单相的CsCl型晶体结构, 具有立方形貌, 平均晶粒尺度为30 nm. 光吸收实验结果表明, 随着Eu掺杂量的增加, 纳米NdB6透射光波长从629 nm红移至1000 nm以上, 表现出了透射光波长的可调特性.
潘晓剑 +5 more
semanticscholar +1 more source
核爆炸的大部分能量是以X射线形式释放的,研究X射线辐射特性对于天基核爆事件监测,当量反演都具有一定参考价值。根据核爆炸X射线能谱特性,构建了黑体辐射模型;根据NRLMSIS大气模型成分数据和高度密度数据,构建大气分层数值模型,并结合NIST数据库,构建分层大气质量吸收系数模型,提高了大气模型与大气质量吸收系数模型准确度。使用数值模拟程序对X射线在大气中的传输特性进行研究,模拟在临近空间高度核爆炸产生的X射线经过大气吸收后的能谱特性以及不同海拔高度点位的能注量。结果表明,在检测点高度恒定的情况下 ...
吕 致辉 +4 more
doaj +1 more source
Constitutive model and dynamic deformation behavior of 800 MPa grade cold-rolled dual phase steel [PDF]
The Hopkinson experiment system was used to do the dynamic tensile experiment of 800 MPa grade cold rolled dual phase steel (DP800). The strain rate was determined as 500, 1000 and 2250 s-1 By comparing the experimental results, both the yield strength ...
CAI Heng-jun +3 more
core +1 more source
铋纳米片作为一种新型二维材料, 具有合适的带隙、较高的载流子迁移率和较好的室温稳定性, 加上优异的电学和光学特性, 是实现中红外脉冲激光的有效调制器件. 中红外单晶光纤兼备晶体和光纤的优势, 是实现高功率激光的首选增益介质. 本文采用超声波法成功制备了铋纳米片可饱和吸收体, 并首次将其用于二极管抽运Er:CaF2单晶光纤中红外被动调Q脉冲激光器中.
郝倩倩 +8 more
semanticscholar +1 more source
V高掺杂量对ZnO(GGA+U)导电性能和吸收光谱影响的研究
目前,在V高掺杂ZnO中,当V掺杂量摩尔数为0.031250.04167的范围内,掺杂量越增加,电阻率越增加或越减小的两种实验结果均有文献报道. 为解决这个矛盾,本文采用密度泛函理论的第一性原理平面波超软赝势方法,构建未掺杂ZnO,V高掺杂的Zn1-xVxO (x=0.03125,0.04167) 两种超胞模型,首先,对所有体系进行几何结构优化,在此基础上,采用GGA+U的方法,计算所有体系的能带结构分布、态密度分布、吸收光谱分布.
侯清玉, 吕致远, 赵春旺
semanticscholar +1 more source
波长调制-直接吸收方法在线监测大气中CH 4 和CO 2 浓度
波长调制-直接吸收光谱(WM-DAS), 同时具有直接吸收光谱(DAS)的免标定、可测量吸收率函数的优点和波长调制光谱(WMS)高信噪比、抗干扰能力强的优点. 本文利用免标定、高信噪比的WM-DAS方法结合长光程Herriott池, 在常压常温条件下, 对大气中CH4 (6046.952 cm–1)和CO2 (6330.821 cm–1)分子两条近红外吸收谱线的吸收率函数进行了测量, 其光谱拟合残差标准差可达到5.6 × 10–5.
王振, 杜艳君, 丁艳军, 彭志敏
semanticscholar +1 more source
SrZn 2 (PO 4 ) 2 :Sn 2+ ,Mn 2+ 荧光粉的发光性质及其能量传递机理
采用高温固相法制备了SrZn2(PO4)2:Sn^2+(SZ2P:Sn^2+),SrZn2(PO4)2:Mn^2+(SZ2P:Mn^2+),SrZn2(PO4)2:Sn^2+,Mn^2+(SZ2P:Sn^2+,Mn^2+)荧光粉.通过X射线衍射、激发和发射光谱详细研究了荧光粉的物相和发光性质.在SrZn2(PO4)2基质中,Sn^2+离子发射光谱是峰值位于461nm宽带谱,归属于Sn^2+离子的3^P1→1^S0能级跃迁,SZ2P:Mn^2+激发光谱由基质吸收带(200—300nm)和位于352,373,
Xiaogang Xiong +5 more
semanticscholar +1 more source
Influence of pore structure features on the high temperature tensile strength of coke [PDF]
Through measuring the pore structure features of coke reacted with H2O or CO2 using a mercury porosimeter,the influence of average pore size,specific surface area and pore size distribution on the high temperature tensile strength of coke were studied in
GUO Wen-tao +5 more
core +1 more source

